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HBase >> mail # user >> Disable timestamp in HBase Table a.k.a Disable Versioning in HBase Table


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Re: Disable timestamp in HBase Table a.k.a Disable Versioning in HBase Table
>
> Is this feature going to be part of any future release of HBase?

i couldn't get it finished in time for 0.94, but i think it's very likely
to be in 0.96, possibly with a backport to .94.  Scan speed should improve
if i have time to optimize the cell comparators and collators
On Tue, May 29, 2012 at 4:29 PM, anil gupta <[EMAIL PROTECTED]> wrote:

> Hi All,
>
> Sorry for late reply as i got stuck in other task at work on Friday and
> skimming through the HBase-4676 took me a while.
>
> HBase-6093 seems to be very close to my suggestion. The only difference is
> that Matt mentioned in the description that it can only be used when all
> inserts are type=Put. Is aforementioned restriction due to HFileV2? I think
> deleting an entire row wouldn't be a problem. right? I have very little
> knowledge about HFileV2. I will try to read about HFileV2 soon.
>
> HBASE-4676 seems really cool. IMHO, currently the issue is that write and
> scan(slower by ~2x as compared to NONE if we assume that Trie compresses by
> ~2-3x) are slow and as per the jira if ratio of value/Key is big then trie
> wont have any impact. Is this feature going to be part of any future
> release of HBase?  Awesome stuff Matt.
>
> @Anoop: You meant that i should use the feature in HBase-4676 and pass the
> timestamp as 0L in each put. Right?
>
> Thanks all for your valuable time and inputs.
> -Anil
>
>
> On Thu, May 24, 2012 at 11:22 PM, Matt Corgan <[EMAIL PROTECTED]> wrote:
>
> > Hi Anil,
> >
> > I created HBASE-6093
> > <https://issues.apache.org/jira/browse/HBASE-6093>with an idea that
> > could solve this problem.  It could be a simple
> > implementation for simple workloads, but gets harder to support for
> tables
> > with TTL's, maxVersion > 1, Deletes, etc...  Maybe it can only be enabled
> > if the other ColumnFamily settings are compatible.
> >
> > Matt
> >
> >
> > On Thu, May 24, 2012 at 9:37 PM, Ted Yu <[EMAIL PROTECTED]> wrote:
> >
> > > What Anoop said is in 0.94.0
> > >
> > > For trunk, HBASE-4676 provides trie data block encoding.
> > > It suits write-once read-many use case very well.
> > >
> > > Cheers
> > >
> > > On Thu, May 24, 2012 at 5:57 PM, Anoop Sam John <[EMAIL PROTECTED]>
> > > wrote:
> > >
> > > > Hi Anil,
> > > >           There is no way you can avoid the timestamp with KVs. In
> your
> > > > case you can think of using data block encoding? You can see
> > > > FastDiffDeltaEncoder and DiffKeyDeltaEncoder. This includes way of
> > > avoiding
> > > > writing the 8 bytes into each KV for timestamp. Still some bytes will
> > be
> > > > written though and this will be done at the block level. Also pls
> note
> > > that
> > > > these encoders will do much more things than the timestamp space
> > > > optimization. Also you need to make sure to pass some timestamp in
> your
> > > > Puts. May be better make as 0L. Else in RS side HBase will assign the
> > cur
> > > > time as the timestamp.  Hope when u read the javadoc for these
> encoder
> > > > classes, u will be more clear.
> > > >
> > > > The one you are telling abt having a feature to fully avoid the
> > timestamp
> > > > is a topic to discuss
> > > >
> > > > Hope I make it clear to you
> > > >
> > > > -Anoop-
> > > > ________________________________________
> > > > From: anil gupta [[EMAIL PROTECTED]]
> > > > Sent: Friday, May 25, 2012 3:21 AM
> > > > To: [EMAIL PROTECTED]
> > > > Subject: Disable timestamp in HBase Table a.k.a Disable Versioning in
> > > > HBase Table
> > > >
> > > > Hi All,
> > > >
> > > > We are planning to store data in HBase. Currently, in one of our use
> > case
> > > > once a row is written into HBase Table we wont be modifying the data
> of
> > > > that row. Since, for every cell(right?) in HBase a timestamp(long
> > value)
> > > is
> > > > stored; this would take up extra 8 bytes. I was thinking is there a
> way
> > > to
> > > > disable timestamp on HBase table when versioning is not required. I
> > went
> > > > through the documentation and searched mailing list for same but